Remove outdated code for common.mode==='subscribe'

[mcm1957]

common.mode 'subscribe' is no longer supported. So the related code should be removed.

At least this is obsolete - but maybe more locations effected:

    // Stop only if subscribe mode
    //noinspection JSUnresolvedVariable
    if (adapter && adapter.common && adapter.common.mode === 'subscribe') {
        adapter.__stopTimer = setTimeout(() => {
            adapter.__stopTimer = null;
            adapter.stop();
        }, 30000);
    }